Hoist braking mechanism



Aprii 16, 1935. E. E. GREVE I HOIST BRAKING MECHANISM v Filed Sept. 15, 1950 4 Sheets-Sheet l April 16, 1935. E, E GREVE 11397 727 HOIST BRAKING MECHANISM Filed Sept; 15, 1930 4 Sheets-Sheet 2 INVENTOR W/Elfi? q April 16, 1935. EE. GREVE HOIST BRAKING MECHANISM Filed Sept. 15, 1930 4 Sheets-Sheet 3 April 16, 1935. E. E. GREVE 1,997,727

HOIST BRAKING MECHANISM Filed Sept. 15, 1950 4 Sheets-Sheet 4 INVENTOR Z BWMSWMELLM Patented Apr. 16,1935 w UNITED STATES PATENT OFFICE nolsr BRAKING MECHANISM Edgar E. Grove, Bellevue, Pa., assignor, by mesne assignments, to Oil Well Supply Company, Oil City, Pa., a. corporation of New Jersey Application September 15, 1930, Serial No. 481,998

7 r I V 2 Claims. (01. 188-77) I This application relates to braking mechanism As above explained, I wish to describe my in- -of the type which is employed for controlling the vention as applied to a hoisting drum used in well paying out of cable or the likefrom a hoist drum. drilling; and I have therefore shown in the draw- Ihis invention deals particularly with the ad- 'ings, not as limiting my invention but for the V justment of, the means for applying afriction purpose of illustrating the same, one embodiment 5 15 its use in-well drilling.

braketo thebrake drum, this'adjustment varying which the same may assume; and accordingly the braking effect produced by the application of Fig. 1' shows in perspective. a pair of friction a forcewhich may be constant. 'This invention brake bands for a hoist drum, the supports for had its origin in the solution of a problem in conthe drum, and operating mechanism for the trolling a hoisting mechanism used in well drillfriction bands;

ing, and although the invention is applicable Fig. 2 shows in plan the operating mechanism broadly to many types of hoisting mechanisms it for the brake bands, the latter being broken away is'believed that it will facilitate understanding to facilitate illustration;

of the invention to describe it in connection with Fig. 3 showsin section and partially in side e v elevation, a portion of the operating mechanism The weights which are involvedin hoisting and for one brake band, this view being a vertical lowering strings of drill tubes in a well which section taken on the line 3-3 of Fig. 2; 7

may reach to as great a depth as eight or nine Fig. 4 shows a force diagram of the braking thousand feet are very great; and great difficulty effect with the operating mechanism in three has been experienced in succeeding in making different positions; 7 20 the brake hold in a satisfactory and safe manner Fig. 5 is a view in side elevation of the hoisting when cable is being unwound from the hoisting mechanism, the derrick floor being shown in secdrum. It is obvious that when the first few 'tion. lengths of tubing are suspended and are being In the illustrative embodiment shown in the lowered in the well,the braking effect need not drawings, the hoisting drum 5 is supported on two 25 b n y as vgreat as when additional lengths vertical posts 6 and 1 which extend upwardly at oftubing have been added to the string so as to the side of the derrick floor 8. A pair of fricreach to a much greater depth'in the well. It is, tion brake bands 9 and iii are provided for conmoreover, desirable that the mechanism for aptrolling the rotation of the hoisting drum so as plying h brak be so arran d tha a wei ht may to pay out the cable when the string of drill tub- 30 be h m the l app y the'b ake, this ing is being lowered in the well. A supporting weight being just sufficient to permit the hoist base such as the plate I! is secured to the derrick drum to slowly revolve, thereby lowering the floor 8. A- pair of spaced lugs 12 are provided drill string in the well. 'It is clear, therefore, for anchoring the end of each brake hand, these at if the brake pp mechanism S P lugs being fixed to the support plate I I in spaced 35 -5 panying claims.

ate au ma C y, t s We ght must have agrealr position so that the anchor members !3 of the or ct v bra action as the weight ofthe brake bands maybe inserted between the same drill pipes suspended in the well increases. and pivoted thereto as at' H. To the free end of Oneobject of my invention is to provide in each brake band is attachedia connecting mem- 40 mb nation With a friction brake, means for apber, such as the tension rod I5 which is pivoted 4O plying the brakeconnected thereto by a member, to the brake band'as at 56. While I have illusthe pp y g means including a a k adjustab y trated a braking mechanism in which the brake connected to the member so that the angle bebands are applied by a tension rod, it is to be tween the crank and the member may be varied. understood that my invention is applicable to A further object of my invention is to provide a other types of friction brakes such, for example, 45 common support for theanchor for the brake as a brake in which a rod is'pushed instead of band of braking means for a hoist drum, and also pulled; and it will become apparent during the the operating mechanism for the brake band, this course of the ensuing description that the same supporting means being provided with spacing principles apply. in the case where the rod is to means engaging the drumsupport to properly'pobe pushed as apply in the embodiment illus- 50 sition one support relative to theother. Further trated in which the rod I5 is to be pulled. objects of my invention will become apparent in The brake applying mechanism includes a the course of the following description and will frame member H in which is pivoted a jack shaft be more particularly pointed out in the accomi8. A lever I9 is fixed to the shaft l8 so that 7 when the lever is is, forced downwardly, torque Car is applied to the shaft I. An angle may be secured to the lever l9 as by welding to enable the operator to use his foot in pressing down on this lever. The outer end of the lever I9 is forked as at 2| to permit a weight 22 to be hung therefrom.

The other end of the jack shaft I8 extends through and is pivoted in a second frame member 23. The projecting end of the shaft carries a sector member 24, which normally extends vertically from the jack shaft. The frame members l1 and 23 are also provided with bearings 25 and 26 respectively; and a crank 21 is mounted in the bearing 25 and a crank 28 is mounted in the hearing 26. The shaft 29 to which the crank 28 is secured extends through the bearing 26; and on the other side of this bearing a crank 3!! is secured. To its upper end is pivoted a link 3|. The other end of the link 21 carries a pin 32 which may be selectively inserted in any one of the holes 34, a plurality of which are provided in sector member 24. As illustrated, these holes are all at the same radial distance from the axis of the jack shaft l8; but it is to be understood that this is not necessary, since the braking effect may be further varied by changing the distance of these perforations from the axis of the jack shaft I. A yoke 36 is slidable on the outer end of the tension rod I5, this yoke being provided with trunnions 31 which extend through the ends of the cranks 21 and 28. An adjusting nut 88 is threaded on the end of the tension rod l5 so as to adjust the yoke 36 longitudinally thereof.

The shaft 29 extends to another crank mechanism similar to the one just described. This crank mechanism includes but a single frame member 40 having a bearing 4| in which is pivotally mounted the stub shaft of a crank 42. A companion crank 43 is secured to the end of shaft 29; and the trunnions of a yoke 44 are mounted in the ends of the cranks 42 and 43. The yoke 44 is slidable longitudinally of the tension rod i5 which is connected to the brake band I. and a nut 45 determines the position of the yoke 44 relative to the tension rod I5 similarly as in the crank mechanism first described.

The frame members I1, 23 and 40 are all secured to the plate II as by bolts 4. The plate H is provided with spacing means 41 which, in the embodiment illustrated herein are formed integrally with the plate. The upturned ends 48 of the spacing means are secured as by bolts to flanges of the posts 6 and 1 thereby anchoring the plate II in proper position relative to the hoisting mechanism.

It will be understood that other securing means than bolts may be employed but, in any event, the upturned ends 48 are to be positioned only at fixed stations on the posts 6 and I so that the relative position of the plate H to the posts and thus to the drum and its brake flanges is accurately fixed. For example, the bolt holes and their position on the flanges of the posts 3 and 1 form fixed stations on these flanges on which the upturned ends 48 must rest when secured by bolts passing through the bolt holes.

In Fig. 4 there is shown a force diagram which illustrates how adjustment of the nuts 88 and 45 along the rods 15 causes the effective action of the bands 9 and II to be changed. F may be taken as the pressure on the lever is including the weight of the lever itself. A may be taken as the length of the lever arm l3. B may be taken as the perpendicular distance from the axis of the jack shaft E8 to the center line of the link 3|, this center line being the one passing through the centers of its two pivots. C may be taken as the vertical distance from the axis of the bearings 25 and 26 to the center line of the link 3|. D may be taken as the vertical distance from the axis of the bearings 25 and 26 to the center line of the rod I5, this center line being taken as extending through the two pivots of the rod l5. P may be taken as the pull on the brake band.

As three different holes 34 are shown in the sector member 24, three examples will be given as illustrating how the pull on the brake band may vary. P, in each case, will equal the product of F times A times C divided by the product of B times D. In each case, F will be taken as 75 pounds and A will be taken as 52 inches. With the crank mechanism in the position shown in Fig. 3, and B taken as 4 inches, C taken as 7 inches and D taken as 2?; inches, P (pull on brake band) will be 1092 pounds. In the middle position, with B equal to 5% inches, C equal to H inches, and. D equal to 3% inches, the calculation of P (pull on brake band) works out as 1518 pounds. With the pin 32 in the third hole and B equal to 6 inches, C equal to 7% inches and D equal to 4% inches, P is calculated to be 2658 pounds.

It is obvious that various factors contribute towards the above calculated increase in pull on the brake band. It is clear that the change in the angle of the cranks 21 and 22 relative to the rod l5 cause a change in the pull on the brake band if the weight 22 be kept the same. This change may, therefore, be the only one relied on to cause the change in the pull on the brake band. The change in the perpendicular distance 15 and the change in the perpendicular distance C also contribute, and it is to be understood that these, as contributing further to the desired purpose, are to be understood as forming a part of more specific features of my invention.

It is moreover clear that by incorporating these principles in my improved brake operating mechanism I have provided a mechanism which, while keeping the lever I 3 in the'same angular position and retaining the same weight 22, provides different braking effects. It should be noted at this point that the angle of the lever is is not altered by the adjustments above described since at thev same time that the nut 38 is adjusted along the tension rod l5, the pin 32 is inserted in a different hole 34, these two changes compensating each other so that the rod l9 maintains its same relative angular position.

It is furthermore apparent that by mounting the various parts of the brake operating mechanism, together with the anchors for the brake bands on the same plate H, the assembling of the hoisting mechanism in proper position on the derrick floor is facilitated. The spacing means 41 engage the supports 6 and I for the hoisting drum and, therefore, the plate with the parts supported thereby are properly positioned relative to the hoisting drum. Since these parts are not being assembled in the factory but are being erected out in the field with rough equipment, the advantage of the provision of the spacing means 41 is obvious.

While I have illustrated and described one specific form of brake applying mechanism, it will be understood that the invention is not restricted to the particular construction and 'arrangement shown, but may be variously modified within the contemplation of the invention and under the scope of the following claims.

I claim:

1. In combination with a friction brake and an operating member therefor, means for applying force tosaid member comprising a crank, adjustable means for connecting the crank to said member at various points along the same whereby the angle between the crank and the adjustable means may be varied, a lever, an actuating weight suspended from the lever, and operative connections between the lever and the crank for transmitting actuating torque from the lever to the crank including an adjustable connection for compensating for adjustments between the crank and the operating member whereby the lever may be maintained at the same angle relative to the horizontal.

2. In combination with a friction brake and an operating member therefor, means for applying force to said member comprising a crank, adjustable means for connecting the crank to said member at various points along the same whereby the angle between the crank and the adjustable means may be varied, a lever, an actuating weight suspended from the lever, and operative connections between the lever and the crank for transmitting actuating torque from the lever to the crank including a link, and a sector member provided with a plurality of perforations to which the link may be pivoted whereby adjustments between the crank and the operating member may be compensated for so as to maintain the lever at the same angle relative to the horizontal.

EDGAR E. GREVE. 

